SplitAtlas

LG / Multi F R-32

LG Multi F 18k R-32 208/230V 2-Zone Mini-Split

Certified capacity
18,000 BTU/h[2]
SEER2
22.5 SEER2[2]
Heating floor
-4 F[1]
Voltage
230 V[1]
Install path
Professional install

The LG Multi F 2-Zone 18k (KUMXB181A) is one of the most efficient multi-zone condensers we list - a certified nominal SEER2 of 22.5 (all-non-ducted) on current R-32 refrigerant, feeding two indoor heads from one 208/230V outdoor unit. Like the rest of LG's multi-zone line it is stocked at retail, so you can buy the equipment (professional installation still applies).

ENERGY STAR certified, with heating that recovers modestly at 5F. A strong value-and- efficiency two-zone.

2 zonesProfessional installCurrent

Refrigerant generation

R-32 - current-generation refrigerant

Dealer-installation warranty note

Buying online can keep warranty coverage only when the seller is expressly authorized by LG; confirm that status and the qualified installation path before purchase.

Installation condition: The online source must be expressly authorized by LG; the system must also satisfy LG's qualified-system installation terms.

Dealer path: Expressly authorized LG source with qualified installation by a trained, licensed HVAC contractor under LG warranty terms.

Paid link

$1,973 / Fresh price - checked Jul 28, 2026

Check price at HVACDirect

This system's warranty depends on licensed installation — get quotes from installers in your area.

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Error Codes
LG Multi F 2-Zone 18,000 BTU R-32 208/230V (KUMXB181A)

Image: LG

Data completeness: 97%
Last sourced
Jul 28, 2026

SplitAtlas score

8.0 / 10

Methodology
Cooling efficiencyAbove average

(22.5 SEER2) among 18k systems

Heating efficiencyBelow average

(9.8 HSPF2) among 18k systems

Cold-weather performanceBottom quartile

(71.8% heat retained at 5F; -4 F heating floor) among 18k systems

WarrantyAbove average

(10 yr parts / 10 yr compressor) across the catalogue

Feature setBelow average

(4 verified features) across the catalogue

Price-to-performanceBelow average

($1,973 median retail) among 18k systems

Documentation & partsBelow average

(7 manuals; spec sheet) across the catalogue

Not evaluated

  • Installation accessibility — not applicable (professional install)N/A

    professional install - DIY-accessibility not applicable

Key ratings

Rated cooling

18,000BTU/hNon-Ducted Indoor Units[2]

Rated heating

22,000BTU/hNon-Ducted Indoor Units[2]

Buyer review snapshot

Best for / skip if

Best for

  • 2-zone projects in the 18k outdoor capacity class.
  • High-efficiency shortlists; SEER2 is 22.5.

Install difficulty

Complex professional install
  • Electrical: 230V; MCA 16.1 A; breaker/fuse 20 A.
  • Line set: connection type not sourced; precharged 65.6 ft; max 164 ft.
  • 2-zone condenser; indoor-head matching and branch layout are part of the job.

Alternatives

Availability and price context

  • Verified current price: $1,973.00 at HVACDirect; availability in_stock; checked Jul 28, 2026. Dealer-installation condition: The online source must be expressly authorized by LG; the system must also satisfy LG's qualified-system installation terms..

Purchase channel policy

LG allows the online-purchase path only when the online source is expressly authorized by LG; an online purchase from a non-authorized source voids the limited warranty.

Warranty impact
The limited warranty is void and LG has no liability when the system is purchased online from a source not expressly authorized by LG.
Installation condition
The online source must be expressly authorized by LG; the system must also satisfy LG's qualified-system installation terms.
Authorized channel
Expressly authorized LG source with qualified installation by a trained, licensed HVAC contractor under LG warranty terms.

Buying online can keep warranty coverage only when the seller is expressly authorized by LG; confirm that status and the qualified installation path before purchase.

Compare online-purchase warranty rules by brand

Source: LG Electronics U.S.A., Inc.: LG R32 Residential / Light Commercial Systems Warranty Card; retrieved Aug 15, 2026.

Source date

Model data sourced
Jul 28, 2026
Page reviewed
Jul 28, 2026
Source-backed records
4
Newest source retrieved
Jul 28, 2026

Warranty tiers

Warranty: 5 years parts and 7 years compressor as standard; 10 years parts and compressor if qualified registered installation.

Review methodology

Model context

Installation context
Multi-zone low-load behavior depends on the indoor heads and how many zones are calling at once.

Strengths

  • Among the highest multi-zone efficiency we list: certified nominal SEER2 22.5 / EER2 13.5 / HSPF2 9.8, ENERGY STAR certified.
  • Buyable equipment (stocked and priced at retail), not dealer-only, on current R-32.
  • Two rooms from one outdoor unit and one circuit.
  • LG's inverter platform and dealer service network.

Weaknesses

  • Professional installation still required - it is equipment you buy, not a DIY kit.
  • Standard Multi F: for guaranteed deep-cold heating, the LGRED version of the 2-zone adds LG's low-temperature heating.
  • Two zones only; three or more rooms need a larger condenser.

Climate suitability

Minimum heating ambient
-4 F[1]
Rated heating at 5F
15,800 BTU/hNon-Ducted Indoor Units[2]
Rated heating at 17F
14,800 BTU/hNon-Ducted Indoor Units[2]
Rated heating at 47F
22,000 BTU/hNon-Ducted Indoor Units[2]

Specifications

Show
Manufacturer
LG
Brand
LG
Product line
Multi F R-32
Model number
KUMXB181A
Indoor unit model
Indoor heads are selected separately on a multi-zone system
Outdoor unit model
KUMXB181A
Number of zones
2
Max indoor units
2 units[1]
Rated cooling capacity
18,000 BTU/hNon-Ducted Indoor Units[2]
Rated heating capacity
22,000 BTU/hNon-Ducted Indoor Units[2]
Voltage
230 V[1]
MCA
16.1 A[1]
Maximum fuse or breaker size
20 A[1]
Breaker needed
not published
SEER2
22.5 SEER2Non-Ducted Indoor Units[2]
EER2
13.5 EER2Non-Ducted Indoor Units[2]
HSPF2 (Region 4)
9.8 HSPF2Non-Ducted Indoor Units[2]
HSPF2 (Region 5)
Certified per indoor-unit combination, not per outdoor unit
COP
not published
COP at 47F
not published
COP at 5F
2.2 COPNon-Ducted Indoor Units[2]
Minimum outdoor heating temperature
-4 F[1]
Minimum outdoor cooling temperature
14 F[1]
Maximum outdoor temperature
118 F[1]
Indoor noise range
Indoor heads are selected separately on a multi-zone system
Outdoor noise rating
54 dBA[1]
Indoor weight
Indoor heads are selected separately on a multi-zone system
Outdoor weight
102.7 lb[1]
Refrigerant
R-32[2]
Refrigerant charge
not published
Manufacturer coverage
not published
Line-set size
1/4 in x 2 liquid / 3/8 in x 2 suction
Included line-set length
Indoor heads are selected separately on a multi-zone system
Maximum line-set length
164 ft[1]
Max line set per indoor
82 ft[1]
Maximum elevation difference
49.2 ft[1]
Max height between indoor units
24.6 ft[1]
Wi-Fi support
Indoor heads are selected separately on a multi-zone system
Energy Star status
ENERGY STAR certified[3]
AHRI certification number
214848481Non-Ducted Indoor Units[2]
Warranty
Standard: 5 yr parts / 7 yr compressor (standard coverage); Best case: 10 yr parts / 10 yr compressor (qualified registered installation). Standard 5-year parts and 7-year compressor coverage; qualified registered installations extend to 10 years total parts and compressor coverage.
Install path
Professional install
Retail price
$1,973.00
Available retailers
HVACDirect
Manual links
AHRI public detail 214848481, LG Multi F R-32 combination data manual, ENERGY STAR exact row 214848481, LG Multi F R-32 current DDepot product page, HVACDirect exact-offer audit for KUMXB181A, KUMXB181A LG Multi F R-32 submittal, LG R32 Residential / Light Commercial Systems Warranty Card
Specification sheet
KUMXB181A LG Multi F R-32 submittal
Last sourced date
Jul 28, 2026

Retail purchase context

Dealer-installation warranty note

Buying online can keep warranty coverage only when the seller is expressly authorized by LG; confirm that status and the qualified installation path before purchase.

Installation condition: The online source must be expressly authorized by LG; the system must also satisfy LG's qualified-system installation terms.

Dealer path: Expressly authorized LG source with qualified installation by a trained, licensed HVAC contractor under LG warranty terms.

Some retailer links may earn us a commission at no extra cost; paid relationships never change scores or recommendations. Affiliate disclosure

Paid link

Dealer-installation warranty note

Buying online can keep warranty coverage only when the seller is expressly authorized by LG; confirm that status and the qualified installation path before purchase.

Check price at HVACDirect

$1,973 / Fresh price - checked Jul 28, 2026

Compatible indoor units

This is an outdoor unit. You choose its indoor heads separately - up to the maximum this condenser supports - and you can mix room sizes and styles across the zones. The models below are the heads this unit is documented to pair with.

  • Concealed ducteds

    9k, 12k

    Model numbers
    • 9k: KNMKB091A
    • 9k: KNUJB091A
    • 12k: KNMKB121A
    • 12k: KNUJB121A

  • Four-way ceiling cassettes

    7k, 9k, 12k

    Model numbers
    • 7k: KNMDB071A
    • 9k: KNUDB091A
    • 12k: KNUDB121A

  • One-way ceiling cassettes

    7k, 9k, 12k

    Model numbers
    • 7k: KNMFB071A
    • 9k: KNUFB091A
    • 12k: KNUFB121A

Sizing note: do not just add up the rooms. Multi-zone condensers have a maximum total connected capacity, and connecting more head capacity than the unit is rated for is a common installer mistake that hurts efficiency and comfort. Match total head capacity to the condenser's rating.

Electrical requirements

Show
Voltage
230 V[1]
Voltage range
208/230V[1]
Phase
1[1]
Frequency
60 Hz[1]
MCA
16.1 A[1]
Breaker needed
not published
Maximum breaker size
20 A[1]
Maximum fuse size
not published
Maximum cooling current
not published
Maximum heating current
not published
Manufacturer wire notes
not published

Installation considerations

Show
Liquid line
1/4 in x 2[1]
Suction line
3/8 in x 2[1]
Line connection type
not published
Precharged length
65.6 ft[1]
Included line-set length
Indoor heads are selected separately on a multi-zone system
Maximum line-set length
164 ft[1]
Max line set per indoor
82 ft[1]
Max height between indoor units
24.6 ft[1]
Indoor dimensions
Indoor heads are selected separately on a multi-zone system
Outdoor dimensions
25.594 x 34.25 x 13 in[1]
Indoor weight
Indoor heads are selected separately on a multi-zone system
Outdoor weight
102.7 lb[1]
Drain size
not published

Related systems and guides

Frequently asked questions

Can I install the LG Multi F 2-Zone 18,000 BTU R-32 208/230V (KUMXB181A) myself, or do I need a pro?
LG Multi F 2-Zone 18,000 BTU R-32 208/230V (KUMXB181A) is built for professional installation: the line set must be flared, evacuated, and charged, which requires EPA-certified refrigerant handling. Installing it outside the manufacturer's requirements can void the warranty, so budget for a qualified HVAC installer.
Will the LG Multi F 2-Zone 18,000 BTU R-32 208/230V (KUMXB181A) keep heating in a cold winter?
The manufacturer publishes 15,800 BTU/h of heating output at 5F. Rated heating operation extends down to -4 F. Certified heating efficiency is 9.8 HSPF2. Match those numbers against your climate's design temperature - in cold regions, output at 5F matters far more than the nameplate capacity measured at 47F.
What electrical circuit does the LG Multi F 2-Zone 18,000 BTU R-32 208/230V (KUMXB181A) need?
Published electrical requirements: 230 V voltage, 16.1 A minimum circuit ampacity, and 20 A maximum breaker or fuse sizing. Confirm the final circuit against the unit nameplate and local code with a licensed electrician.
How far can the outdoor unit be from the indoor head?
The published maximum line-set length is 164 ft, and the included line set comes pre-charged for 65.6 ft. Longer runs than the included set allows typically mean added refrigerant and a pro visit, so measure the planned routing before ordering.
What warranty does the LG Multi F 2-Zone 18,000 BTU R-32 208/230V (KUMXB181A) carry?
The manufacturer publishes these warranty tiers: Standard: 5 yr parts / 7 yr compressor (standard coverage); Best case: 10 yr parts / 10 yr compressor (qualified registered installation). Registration requirements and proof of qualified installation commonly affect coverage, so read the warranty terms before install day.

Data sources

Show
  1. LG Electronics U.S.A., Inc.: LG Multi F R-32 official technical documents for KUMXB181ASourced - manufacturer technical document

    Covers Frequency, electrical_spec.guaranteed_voltage_range, Maximum breaker size, Minimum circuit ampacity, Phase, Voltage and more

  2. Air-Conditioning, Heating, and Refrigeration Institute: AHRI public detail 214848481Sourced - AHRI directory

    Covers AHRI certification number, performance_spec.cold_climate_designation, Rated cooling capacity, COP at 5F, EER2, Rated heating capacity and more

  3. U.S. Environmental Protection Agency ENERGY STAR: ENERGY STAR exact row check for AHRI 214848481Sourced - Energy Star listing

    Covers Energy Star status

  4. LG Electronics U.S.A., Inc.: LG R32 Residential / Light Commercial Systems Warranty CardSourced - manufacturer technical document

    Covers Best-case compressor warranty, Best-case warranty conditions, Best-case parts warranty, Legacy compressor warranty value, Legacy warranty value, Standard compressor warranty and more

  5. LG Multi F R-32 combination data manualSourced - manual

    Covers Manual links

Last updated

Jul 28, 2026